REGARDING your Green Guardian story quoting the Royal Institution of Chartered Surveyors (News Shopper, September 17), I could not disagree more with the payback time for solar thermal (hot water).

I agree solar voltaic (electricity) is not economically viable and deteriorates, but solar thermal is cost effective and will pay for itself sooner rather then later.

Who knows how much our energy prices will go up over the coming years?

But as long as they do keep going up, the time it takes to recoup your investment will diminish — we are looking at less then 20 years and this is being generous to energy suppliers.

This invested money is adding value to your property, so even if you sell your house, you will get your money back.

Consider it a worthwhile investment which will probably generate more interest for your money long term.

MERVYN FERNANDEZ, address supplied